This retrospective observational study aims at the comparison of the tumour-microenvironment tissue architecture before and after neo-adjuvant therapy in samples from HER2-positive (HER2+) breast cancer (BrCa) patients that display residual invasive disease in the breast/lymph node at surgery after standard-of-care combined chemotherapy and trastuzumab treatment.
The working hypothesis of the investigators is that:
Therapy imposes a selective pressure on tumour-microenvironment features promoting resistance to treatment.
Participant that have already undergone neo-adjuvant treatment as part of their regular medical care for HER2-positive breast cancer will provide access to formalin-fixed paraffin-embedded (FFPE) samples taken before and after therapy.
Tumoral, peri-tumoral and stromal regions of each specimen will be analyzed with the ultimate goal to identify new biomarkers (and putative targets) of resistance to therapy.
Participant is willing and able to give informed consent for participation in the study.
Patient underwent the following procedure before surgery: biopsy, sequential chemotherapy comprising treatment with antracyclines (AC/EC q21, 4 cycles) followed by taxanes (paclitaxel 1,8,15 q21 for 12 weeks) in combination with the anti-HER2 antibody trastuzumab.
Specimen collected at surgery display residual invasive disease in the breast/lymph node.
pre-existing conditions or concurrent diagnoses;
concomitant use of other medications during neo-adjuvant treatment;
quality of stored specimen does not meet the standard for Imaging Mass Cytometry analysis.
Giampaolo Bianchini
Lead sponsor
IRCCS Ospedale San Raffaele
Sponsor institution